Project description:The purpose of this study was to examine how Mtb integrates acidic pH and available carbon sources as environmental cues to regulate its metabolism and growth rate. RNA-seq transcriptional profiling of M. tuberculosis growing at acidic or neutral pH, in pyruvate or glycerol, was examined. These studies identified carbon source-dependent and -independent pH-dependent adaptations.
Project description:The purpose of this study was to examine how Mtb integrates acidic pH and available carbon sources as environmental cues to regulate its metabolism and growth rate. RNA-seq transcriptional profiling of M. tuberculosis growing at acidic or neutral pH, in pyruvate or glycerol, was examined. These studies identified carbon source-dependent and -independent pH-dependent adaptations. Mtb strain CDC1551 was grown in standing T-75 flasks in 40 mL of medium seeded an initial OD of 0.1. We examined medium in four conditions pH 7.0 10 mM glycerol, pH 5.7 10 mM glycerol, pH 7.0 10 mM pyruvate, pH 5.7 10 mM pyruvate. Following 3 days of incubation at 37C, RNA was isolated from the bacterial cultures and used for RNA-seq.
Project description:We analyzed the genes expressed, or the transcriptome, of bacilli (Mycobacterium tuberculosis) growing in fatty acids as sole carbon source. Using new technologies to massively sequence of RNA molecules we identified a group of genes that provides novel insight regarding the metabolic pathways and transcriptional regulation of latent M. Tuberculosis.
Project description:We analyzed the genes expressed, or the transcriptome, of bacilli (Mycobacterium tuberculosis) growing in fatty acids as sole carbon source. Using new technologies to massively sequence of RNA molecules we identified a group of genes that provides novel insight regarding the metabolic pathways and transcriptional regulation of latent M. Tuberculosis. Comparative Transcriptomics between two carbon source (Dextrose, Long Fatty Acids), at two states of growth (Exponential and Stationary Phase)
Project description:The success of Mycobacterium tuberculosis (Mtb) is largely due to its ability to withstand numerous stresses imposed by host immunity. Here, we present a data-driven model that captures these adaptive mechanisms and reveals the dynamic interplay of host-derived stresses and genome-encoded regulatory programs in Mtb. The model captures the genome-wide distribution of cis-acting gene regulatory elements and the conditional influences of transcription factors at those elements to elicit environment-specific responses. Analysis of transcriptional responses that may be essential for Mtb’s survival in acidic conditions identified regulatory control by the MtrAB two-component signal system. This data is a comparison of transcriptional differences (RNA-seq) between low pH (pH 5.6) and neutral pH (pH7) of Mtb
Project description:Mycobacterium tuberculosis (Mtb) survives host defenses by adapting to the environmental conditions during infection. A critical survival strategy involves pH homeostasis, mediated by complex signalling systems that regulate metabolic reprogramming and stress responses. While the lysine acetyltransferase Rv0998 is known to support Mtb hypoxia adaptation and metabolic flexibility, its role in acid stress remains unexplored. Here, we investigate how Rv0998 enables acid tolerance by analysing the transcriptomic profiles of the strains under physiological pH (pH 6.8) and acidic pH that mimics phagosomal environment (pH 5.7).
Project description:The purpose of this study was to determine (i) the interplay between Mycobacterium tuberculosis response to acidic pH and cholesterol, two signals experienced concurrently by the bacterium during host colonization, and (ii) the role of the transcription factor Mce3R in regulation of this response.
Project description:Following phagocytosis by macrophages, Mycobacterium tuberculosis (Mtb) senses the intracellular environment and remodels its gene expression for growth in the phagosome. Abramovitch et.al. in this current study identified an Acid and Phagosome Regulated (aprABC) locus that is unique to the Mtb complex and whose gene expression is induced during growth in acidic environments in vitro and in macrophages. The authors propose a model where phoP senses the acidic pH of the phagosome and induces aprABC expression to fine-tune processes unique for intracellular adaptation of Mtb complex bacteria. This study uses microarray analyses to compare transcriptional responses of wild type Mycobacterium tuberculosis (CDC1551) to aprABC locus deletion mutants and the phoP transposon mutant. The bacteria were grown to early log phase in vented T-75 standing flasks containing 12 mL of pH 7.0 7H9 OADC medium. Transcript levels of the wild type bacteria were compared to the following mutants: aprABC null, aprBC null, aprC null, phoP::Tn mutant.
Project description:Bedaquiline (BDQ) is a diarylquinoline antibiotic that targets mycobacterial ATP synthase and is used in the treatment of drug-resistant tuberculosis. Cholesterol is an important carbon source for Mycobacterium tuberculosis during infection and has been shown to influence antibiotic susceptibility. To investigate how the growth environment shapes the transcriptomic response to BDQ, we performed RNA-seq on M. tuberculosis H37Rv cultures grown in standard medium or cholesterol-supplemented medium (0.2 mM) and treated with low-dose (0.625 μg/mL) or high-dose (2.5 μg/mL) BDQ, or DMSO as vehicle control, for 4 hours.
